Syntheses, Crystal Structure, and Magnetic Property of a New Mn(II) Complex with an Aromatic N-heterocyclic Tetracarboxylic Acid Ligand

A new 2D Mn(II) complex named as [Mn3(HL)2(H2O)6]n (I) (H4L = 3-(2,4-dicarboxyphenyl)-2,6-dicarboxypyridine) was synthesized and characterized by IR, elemental analysis, and single-crystal X-ray diffraction method (CIF file CCDC no. 1915189). The complex crystallizes in the monoclinic space group C2/c with Z = 4, a = 20.6597(11), b = 9.0949(5), c = 20.6041(12) A, β = 110.056(6)°. The crystal consists of trinuclear Mn(II) ion clusters {Mn3} which are linked by four independent HL3– ligands and these trimeric units are connected into 2D structure by pentadentate HL3– ligand in alternate bis(bridging) and chelated coordination modes. Thermogravimetry, powder X-ray diffraction, and magnetic measurement experiments are also carried out to determinethe thermal stability, phase purity and magnetism. The results show that weak antiferromagnetic interactions occur between the Mn(II) centers within bridging trinuclear {Mn3} cluster.